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<head>
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div class="a1">321</div>
    <div class="a2">132</div>
    <div id="a3">123</div>
    <b>1234567</b>
</body>
</html>
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    // console.log(b[0]);
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